Impact of Diabetes Mellitus on Outcomes of Patients Undergoing Autologous Stem Cell Transplantation for Multiple Myeloma in the U.S.

Abstract

High dose chemotherapy followed by Autologous Stem Cell Transplant (Auto-SCT) is considered standard of care for most patients with Multiple Myeloma (MM) in the U.S. However, recent evidence suggests that diabetic patients with MM are less likely to receive Auto-SCT due to concerns for higher toxicity. We sought to determine the impact of diabetes on in-hospital outcomes of MM patients undergoing autoSCT. We queried the Nationwide Inpatient Sample (NIS) from the years 2009-2011 to identify all adult hospitalizations with MM and auto-SCT. Diabetic status was ascertained using ICD-9 diagnostic codes. Primary and secondary outcomes were in-hospital mortality and length of stay (LOS) or costs of hospitalization (COH) respectively. Univariate methods included chi-square test and t-test where appropriate. Multivariate analysis was done using Generalized Linear Mixed Models (GLMM) to account for clustering in the dataset. All p values were two sided and level of significance was chosen at 0.05. A total of 2868 (14,153 estimated) hospitalizations for MM related auto-SCT was identified, out of which 13% had diabetes. The mean age was 58 ± 8.7 years, 43% females and 67% whites. The overall in-patient mortality rate was 1.78% whereas mean LOS and COH was 17 days and $160,720 respectively. Diabetes did not impact inpatient mortality (1.31% vs. 1.85%; p 0.45), LOS (18 vs. 17.6 days; p 0.33) or COH ($160,665 vs. $160,728; p 0.99). Similar results were seen on GLMM for in-hospital mortality (adjusted Odds Ratio, aOR 0.67; 95% CI 0.26-1.75; p 0.42) after adjusting for patient (age, sex, race, comorbidity, insurance status) and hospital characteristics (bedsize, location, teaching status). Our large U.S. population-based study suggests that diabetic patients with MM undergoing Auto-SCT have similar in-hospital outcomes compared to their nondiabetic counterparts. Future studies should explore the incidence of other treatment related complications in this population. Disclosure K. Siwakoti: None. S. Giri: None. V. Bhatt: None.